Coupling element cooling arrangment

ABSTRACT

A rotating system includes a drive member and a driven member. The rotating system includes a coupling positioned to rotatably couple the drive member to the driven member and a housing surrounding a portion of the coupling to define an inside and an outside, the housing having a plurality of apertures. A fan is coupled to the coupling and operable to produce a flow of air from the inside to the outside via at least one of the plurality of apertures, and a guide tube is positioned within one of the plurality of apertures to guide a flow of air from the outside to the inside.

RELATED APPLICATION DATA

The present application is a continuation of U.S. patent applicationSer. No. 11/939,133 filed Nov. 13, 2007, now U.S. Pat. No. 8,333,574.

BACKGROUND

The present invention relates to a system for cooling a coupling elementpositioned between a drive member and a driven member. Morespecifically, the present invention relates to a cooling system for aflexible coupling positioned between a drive member and a driven member.

Couplings are generally employed between rotating equipment to connectthem for rotation. The couplings allow different drive members to drivethe different driven members without extensive modifications. In oneexample, an engine drives a compressor to produce a flow of compressedfluid.

Often, flexible couplings are employed to allow for slight misalignmentof the shafts, to damp vibration (rotational and/or axial), or otheroperating conditions that may be problematic with a more rigid coupling.However, movement of the coupling to accommodate misalignment orvibration can produce heat. Air is sometimes directed to the coupling toreduce the operating temperature of the coupling. However, conventionalmethods sometimes direct less air to the coupling than desired, therebyallowing the coupling to operate at a temperature above a desiredtemperature. The increased operating temperature of the coupling canreduce the operating life of the coupling.

SUMMARY

In one embodiment, the invention provides a rotating system including adrive member and a driven member. The rotating system includes acoupling positioned to rotatably couple the drive member to the drivenmember and a housing surrounding a portion of the coupling to define aninside and an outside, the housing having a plurality of apertures. Afan is coupled to the coupling and operable to produce a flow of airfrom the inside to the outside via at least one of the plurality ofapertures, and a guide tube is positioned within one of the plurality ofapertures to guide a flow of air from the outside to the inside.

In another embodiment, the invention provides a rotating system thatincludes a drive member, a driven member, and a coupling operablypositioned between the drive member and the driven member to rotatablycouple the drive member to the driven member. A fan is operable toproduce a low pressure region and to direct cooling air from the lowpressure region to the coupling. A guide tube has a first end positionedto direct the cooling air to the second end positioned within the lowpressure region.

In another embodiment the invention provides a rotating system thatincludes an engine, a compressor; and a flexible coupling positionedbetween the engine and the compressor to rotatably couple the engine andthe compressor. A housing surrounds a portion of the coupling. Thehousing has a plurality of apertures. A fan is operable to produce a lowpressure region and to direct cooling air from the low pressure regionto the coupling. A guide tube has a first end positioned to direct thecooling air to the low pressure region. The guide tube extends throughone of the plurality of apertures and is separate from the housing.

Other aspects of the invention will become apparent by consideration ofthe detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a compressor system embodying theinvention;

FIG. 2 is an exploded perspective view of a portion of the compressorsystem of FIG. 1; and

FIG. 3 is a schematic cross-section of a portion of the compressorsystem of FIG. 1.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the following drawings.The invention is capable of other embodiments and of being practiced orof being carried out in various ways. Also, it is to be understood thatthe phraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including,” “comprising,” or “having” and variations thereof herein ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items. Unless specified or limited otherwise, theterms “mounted,” “connected,” “supported,” and “coupled” and variationsthereof are used broadly and encompass both direct and indirectmountings, connections, supports, and couplings. Further, “connected”and “coupled” are not restricted to physical or mechanical connectionsor couplings.

FIG. 1 illustrates a compressor system 10 that includes a drive member15, such as an engine, a driven member 20, such as a compressor, and acoupling 22 that connects the compressor 20 to the engine 15 such thatthe engine 15 drives the compressor 20. In the illustrated construction,the engine 15 includes an internal combustion engine or a diesel engine.However, other constructions may include other combustion engines suchas rotary or radial engines, combustion turbine engines, and the like.In still other constructions, electric motors or other drive devices areemployed. As such, the invention should not be limited by the type ofdrive member 15 employed so long as the drive member 15 includes a driveshaft 25 (shown in FIG. 2).

The engine 15 also includes an engine mounting face 30 positionedadjacent the drive shaft 25 and sized to allow for attachment of thedriven member 20. In the illustrated construction, the engine mountingface 30 includes a substantially planar circular surface having aplurality of apertures 35 formed therein.

The driven member 20 can include a number of devices such as but notlimited to a compressor, a pump, or a generator. In the illustratedconstruction, the driven member 20 includes a rotary screw compressor.Of course other types of compressors (e.g., centrifugal, scroll,reciprocating, etc.) could be employed if desired.

The compressor 20 includes a substantially stationary housing 40 thatsupports one or more moving elements disposed within the housing 40. Inthe case of the rotary screw compressor 20, the moving elements includea pair of intermeshing screw members. One of the screw members is drivenby a shaft 45 (shown in FIG. 2) that extends from the housing 40.

The compressor 20 also includes a bell housing 50 that is attached to,or is formed as part of the compressor housing 40. The bell housing 50includes a compressor mounting face 55 disposed around the shaft 45. Thecompressor mounting face 55 is a circular substantially planar surfacethat includes a plurality of apertures 60. The mounting face 55 isarranged to allow the bell housing 50 to engage the engine mounting face30 to connect the bell housing 50 and the compressor 20 to the engine15. A plurality of bolts 65 pass through the apertures 60 in thecompressor mounting face 55 and threadably engage the apertures 35 inthe engine mounting face 30 to attach the stationary portion of thecompressor 20 to the stationary portion of the engine 15.

With reference to FIG. 2, the bell housing 50 includes a wall 70 thatseparates an inside 75 or coupling space, from an outside 80 and definesa plurality of apertures 85 that extend through the wall 70 to providefor fluid flow between the inside 75 and the outside 80. In theillustrated construction, four substantially rectangular apertures 85are formed through the wall 70 with other shapes or quantities ofapertures also being possible. The compressor mounting face 55 ispositioned at a large diameter end of the wall 70.

As noted, the wall 70 of the bell housing 50 is shaped such that thebell housing 50 cooperates with the engine to define the coupling space(the inside 75). The coupling 22 is disposed within the space 75 suchthat the bell housing 50 covers the coupling 22 and inhibits access tothe rotating components between the engine 15 and the compressor 20.

With reference to FIGS. 2 and 3, the coupling 22 includes a gear 90, acoupling member 95, a flywheel 100, a fan 103, and a drive plate 105.The illustrated gear 90 is a spur gear that is fixedly attached to thecompressor shaft 45. In the illustrated construction, a key 110 is usedto rotationally couple the gear 90 and the shaft 45. Of course, otherconstructions could employ other systems to rotationally couple the gear90 and the shaft 45. It should be noted that while a spur gear 90 isillustrated in FIGS. 2 and 3, other constructions could employ a splineor other arrangement if desired.

The coupling member 95 includes a gear portion 115 that defines an inneraperture shaped to receive the gear 90 such that the gear 90 and thecoupling member 95 are rotationally coupled. However, the engagementbetween the gear 90 and the gear portion 115 allows for relative axialmovement of the coupling member 95 with respect to the gear 90 and thecompressor 20. The coupling member 95 also includes a plate portion 116that connects to the gear portion using a flexible portion 117. Theplate portion includes a plurality of apertures that are sized andpositioned to receive bolts 118 that facilitate the attachment of thecoupling member 95 to the flywheel 100. The flexible portion 117 ispreferably formed from a resilient material such as rubber to allow thecoupling to absorb vibrations and flex as required.

The fan 103 includes a disk portion 120 that supports a plurality ofvanes 125. The vanes 125 are arranged to produce air movement whenrotated. Specifically, the vanes 125 are arranged to draw air from theinner most diameter of the vanes 125 and discharge the air to theoutermost portion of the vanes 125. A spacer 126 is positioned betweenthe disk portion 120 and the plate portion 116 to position the fan 103as desired.

The flywheel 100 includes a disk portion 130 that supports a weightedportion 135. The flywheel 100 also includes an engine attachment portion140 and a fan attachment portion 145 that engages the disk portion 120of the fan 103 to fixedly attach the fan 103 to the flywheel 100.

The engine attachment portion 140 includes a plurality of apertures 150arranged to engage the drive plate 105 that is fixedly attached to thedrive shaft 25. Thus, the flywheel 100 is fixedly attached to the driveshaft 25 and flexibly engaged to the coupling member 95. The couplingmember 95 is rotationally coupled to the gear 90 but is free to moveaxially with respect to the gear 90 and the gear 90 is fixedly attachedto the compressor shaft 45 to complete the coupling 22.

Before proceeding, it should be noted that the illustrated coupling 22is one possible coupling arrangement with many other couplingarrangements being possible. The invention described herein is suitablefor use with virtually any coupling 22 that uses a coupling member 95and that is disposed within the coupling space 75.

With continued reference to FIGS. 2 and 3, the compressor system 10 alsoincludes a guide tube 160 positioned in one of the apertures 85 formedin the wall 70 of the bell housing 50. The guide tube 160 defines aninlet 165 positioned outside of the bell housing 50 and an outlet 170positioned adjacent the innermost diameter of the vanes 125. The guidetube 160 is shaped to engage the wall 70 of the bell housing 50.

With the guide tube 160 positioned as illustrated in FIGS. 2 and 3, theguide tube 160 defines a flow path 175 that provides for the passage ofair from the outside 80 to the inside 75. The apertures 85 that do notinclude a guide tube 160 define a second flow path 180 from the inside75 to the outside 80.

In the illustrated construction, the guide tube 160 is simply positionedwithin the aperture 85. However, other constructions may include arestraining member that holds the guide tube 160 in the desiredposition. Still other constructions may employ welding, soldering,brazing, adhesives, and the like to affix the guide tube 160 to the bellhousing 50.

While the illustrated construction includes a single guide tube 160,other constructions may employ two guide tubes 160 or more than twoguide tubes 160 as may be desired. The guide tube 160 can be formed fromany suitable material with plastic or metal being preferred.

In operation, the engine 15 combusts a fuel to produce shaft power atthe drive shaft 25. The drive shaft 25 in turn rotates the flywheel 100which is fixedly coupled to the drive shaft 25. The flywheel 100provides rotational inertia that reduces pulsations in the drive shaft25 caused by the uneven application of power provided by the engine 15.

The gear 90 engages the gear portion 115 formed as part of, or attachedto the coupling member 95 to rotationally couple the gear 90 to thecoupling member 95. The gear 90 remains free to move axially withrespect to the coupling member 95. The gear 90 is fixedly attached tothe driven shaft 45 such that rotation of the gear 90 produces acorresponding rotation of the driven shaft 45.

Rotation of the fan 103 produces a low pressure region 185 near theinnermost portion of the vanes 125 as air is pulled from this region bythe fan 103 and discharged from the bell housing 50 via the apertures85. To improve the effectiveness of the fan 103, cool air from outsideof the bell housing 50 is introduced to this low pressure region 185inside of the bell housing 50 using the guide tube 160. The inlet 165 ofthe guide tube 160 is positioned outside of the bell housing 50 in aregion where the air pressure is approximately equal to atmosphericpressure. The outlet 170 of the guide tube 160 is positioned near theinnermost portion of the vanes 125 where rotation of the fan 103produces the low pressure region 185. Thus, the fan 103 draws cool airfrom outside of the bell housing 50 into the coupling space 75 toimprove cooling of the coupling 22. The remaining apertures 85 remainopen to allow for the discharge of air from the coupling space 75 duringfan operation.

Thus, the invention allows for the efficient introduction of cool airinto the coupling space 75. The fan 103 then directs the cool air overthe coupling 22 to improve cooling of the coupling 22 and reduce theoperating temperature of the coupling 22.

Various features and advantages of the invention are set forth in thefollowing claims.

What is claimed is:
 1. A rotating system including a drive member and adriven member that rotate about an axis, the rotating system comprising:a coupling positioned to rotatably couple the drive member to the drivenmember; a housing surrounding a portion of the coupling to define aninside and an outside, the housing having a plurality of substantiallyidentical outlet apertures each spaced a substantially equal distancefrom the axis and arranged to direct air out of the housing; a fancoupled to the coupling and operable to produce a flow of air from theinside to the outside; and a guide tube positioned within one of theplurality of outlet apertures to guide a flow of air produced by the fanfrom the outside to the inside, such that the guide tube converts theone of the plurality of outlet apertures into an inlet aperture.
 2. Therotating system of claim 1, wherein the guide tube is separate from thehousing.
 3. The rotating system of claim 1, wherein the guide tubesealably engages the housing to inhibit airflow through the aperturebetween the guide tube and the housing.
 4. The rotating system of claim1, wherein the fan includes a plurality of vanes that produce a lowpressure region in response to rotation.
 5. The rotating system of claim4, wherein the guide tube includes a first end in fluid communicationwith the outside and a second end in fluid communication with the lowpressure region to produce a flow of air from the first end to thesecond end in response to rotation of the fan.
 6. The rotating system ofclaim 1, wherein the coupling comprises a polymer.
 7. The rotatingsystem of claim 1, wherein the coupling comprises rubber.
 8. Therotating system of claim 1, wherein the coupling is a flexible coupling.9. The rotating system of claim 1, further comprising a second guidetube positioned in a second of the plurality of apertures.
 10. Arotating system comprising: a drive member; a driven member; a couplingoperably positioned between the drive member and the driven member torotatably couple the drive member to the driven member for rotationabout an axis; a fan operable to produce a low pressure region and todirect cooling air from the low pressure region to the coupling; ahousing surrounding at least a portion of the coupling to define aninside and an outside; and a guide tube having a first end positionedoutside of the housing to direct the cooling air to the second endpositioned within the low pressure region, the guide tube being separatefrom the housing and passing through the housing.
 11. The rotatingsystem of claim 10, wherein the low pressure region is on the inside andthe first end of the tube is positioned outside such that rotation ofthe fan produces a flow of air from the outside to the inside via theguide tube.
 12. The rotating system of claim 10, wherein the housingdefines a plurality of apertures.
 13. The rotating system of claim 12,wherein the apertures at least partially define a first flow path forthe passage of air from the inside to the outside, and the guide tube ispositioned in one of the apertures to at least partially define a secondflow path for the passage of air from the outside to the inside.
 14. Therotating system of claim 10, wherein the coupling comprises rubber. 15.The rotating system of claim 10, wherein the coupling is a flexiblecoupling.
 16. The rotating system of claim 10, wherein the fan includesa plurality of vanes.
 17. The rotating system of claim 10, wherein thedrive member is a diesel engine and the driven member is an aircompressor.
 18. A rotating system comprising: an engine; a compressor; aflexible coupling positioned between the engine and the compressor torotatably couple the engine and the compressor for rotation about anaxis; a housing surrounding a portion of the coupling, the housinghaving a plurality of outlet apertures arranged to direct air out of thehousing, each aperture substantially equidistant from the axis; a fanoperable to produce a low pressure region and to direct cooling air fromthe low pressure region to the coupling; and a guide tube having a firstend positioned outside of the housing to direct the cooling air to thelow pressure region, wherein the guide tube extends through one of theplurality of outlet apertures and is separate from the housing, theguide tube operable to direct air into the housing to convert the one ofthe plurality of outlet apertures into an inlet aperture.
 19. Therotating system of claim 18, wherein the guide tube sealably engages thehousing to inhibit airflow through the aperture between the guide tubeand the housing.
 20. The rotating system of claim 18, wherein theapertures at least partially define a first flow path for the passage ofair from the inside to the outside, and the guide tube at leastpartially defines a second flow path for the passage of air from theoutside to the inside.